ML20100Q598
| ML20100Q598 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 03/12/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20100Q595 | List: |
| References | |
| NUDOCS 9203180054 | |
| Download: ML20100Q598 (2) | |
Text
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NUCLE AR REGULATORY COMMISSION E
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION BELATED TO AMENDMENT NO.154 TO FACILITY OPERATING LICENJE NO. OPR-65 i
NORTHEAST NUCLEAR ENERGY COMPANY THE CONNECTICUT LIGHT AND POWER COMPANY l
THE WESTERN MASSACHUSETTS ELECTRIC COMPANY l
MILLSTONE NUCLEAR POWER STATION. UNIT N0 J DOCKET NO. 50-336
1.0 INTRODUCTION
By application for license amendment dated June 10, 1991, Northeast Nuclear Energy Company (the licensee) requested changes to the Technical Specifications (TS) for Millstone Nuclear Power Station, Unit No. 2.
The proposed amendment would change the Technical Specifications Section No.
4.10.1.2. Special Test Exceptions, Shutdown Margin Surveillance Requirements.
The proposed change would extend the time prior to the reduction of shutdown margin to demonstrate control element assembly (CEA) insertion capability from 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to 7 days.
2.0 EVALUATION Special Test Exception 3.10.1-permits the shutdown margin requirements in Modes 2 and 3 to be suspended for certain low-power physics tests. The Surveillance Requirements (SR) state that each CEA not fully inserted shall be demonstrated capable of full insertion when tripped from at least the 50X withdrawn position within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to reducing the shutdown margin to less than the limits required in Modes 2 and 3 by TS 3.1.1.1.
For Millstone 2, TS 3.1.3.4 also requires tripping the CEAs but for a different purpose.
In this case, the CEAs are tripped in order to verify that CEA drop times are less than the value assumed in the safety analyses. These tests are required following each removal of the reactor vessel head and following any maintenance or modification to the CEA drive system which could affect specific CEAs.
Since these tests are usually performed more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> before the CEA worth measurer..antt ce needed, in practice, the CEAs are tripped at least twice following a reW li') outage:
once for the drop time measurements and once prior to the tir:.ne shutdown margin limit is suspended.
The proposed change would normally require only one such test of the CEAs.
This change is acceptable for several reasons.
First, the probability of a p&3180034920312ADOcK 05000336 PDR
$ stuck CEA is not significantly increased by the change.
Second, there are no changes to core geometry between the time that the CEAs are tripped for the drop time measurements and the time that the shutdown margin limit would be suspended (up to 7 days) because the vessel head and all vessel internah 4
would be in their final position and secured.
Since CEA drop timing tests will be performed within 7 days, with no changes made that would affect the capability of the CEA to trip within this time, the verification of CEA insertion prior to suspending shutdown margin is not required and the proposvi extension to demonstrate CEA insrrtion capability from 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to 7 days is acceptable.
3.0 SJATE CONSULTATION in accordance with the Commission's regulations, the Connecticut State official was notified o' the proposed issuance of the amendment. The State official had no comments.
4.0 ENVIRONMENTAL CONSIDERATION
The amendment changes surveillance requirements. The NRC staff has determined that the ame.idment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure.
The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (56 FR 31439).
Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental essessment need be prepared 11. connection with the issuance of the amendment.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, g
that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the comon defense and security or to the health and safety of the public.
Principal Contributor:
L. Kopp Date:
March 12, 1902 I
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